1. Field of the Invention
The invention relates to a backlight module, and more particularly to a design of a light source in a backlight module.
2. Description of Related Art
In recent years, liquid crystal displays (LCDs) that have been developed to achieve full-color display gradually replace conventional cathode ray tube (CRT) displays and have become mainstream displays in the market due to the advantages of low operation voltages, non-radiation, light weight, small volume occupancy, and so forth. The LCDs are non-self-illuminating displays, and therefore display functions of the LCDs are achieved when the required light is provided by backlight modules. With increasing consciousness of environmental protection, cold cathode fluorescent lamps (CCFLs) serving as light-emitting devices in conventional backlight modules are gradually replaced by light-emitting diode (LED) devices because the LED devices that are more friendly to the environment.
FIG. 1 is a schematic cross-sectional view illustrating a conventional backlight module. With reference to FIG. 1, a conventional backlight module 100 includes a light guide plate (LGP) 110, a plurality of light sources 120, and a plurality of optical clear adhesives 130. The LGP 110 has a light-incident surface 110a and a light-emitting surface 110b opposite to the light-incident surface 110a. Each of the light sources 120 is adhered to the light-incident surface 110a of the LGP 110 via one of the corresponding optical clear adhesives 130, respectively.
As shown in FIG. 1, each of the light sources 120 includes a carrier 120a, a plurality of LED devices 120b, a light-incoupling component 120c, and a plurality of ring-shaped reflectors 120d. The LED devices 120b and the light-incoupling component 120c are configured on the carrier 120a. Light emitted from the LED devices 120b enters the light-incoupling component 120c from the side surface S of the light-incoupling component 120c and leaves the light-incoupling component 120c from a top surface T of the light-incoupling component 120c. The ring-shaped reflectors 120d cover the LED devices 120b and an edge of the top surface T. Besides, the top surface T of the light-incoupling component 120c is adhered to the light-incident surface 110a of the LGP 110 via the optical clear adhesive 130.
As indicated in the region X of FIG. 1, the light emitted from the light source 120 in FIG. 1 is excessively concentrated on top of the light-incoupling component 120c. In addition, a part of the light emitted from each of the LED devices 120b passes through the corresponding optical clear adhesive 120 and is then reflected by the sidewall of each of the ring-shaped reflectors 120d, which causes light leakage as indicated in the region Y of FIG. 1. Accordingly, the conventional backlight module 100 has unfavorable optical uniformity, and said problem requires an effective solution.